Coupling system for high frequency transmitters



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Aug. 30, 1932. L. A. GEBHARD COUPLING SYSTEM FOR HIGH FREQUENCYTRANSMITTERS 2 Sheets-Sheet Al Filed Dec. 22, 1928 F www INVENTOR.

2 A;TORNEY Aug'so; 1932. L. A. GEBHARD 1,874,958

COUPLING SYSTEM FOR HIGH FREQUENCY TRANSMITTERS Filed Dec. 22, 1928 2Sheets-Sheet 2 I TFE- I w @I ih Y INVENTOR. QOMO a, Qia/ Hind Q BY `HMam A TU RNEY '40 transmitter is'caused tooperate. In'zorder Switchmembers 19, 24 and 2.2.are mechani- 9" Patented Aug. 30, 1932 Y l Y y ly* i v I Louis A. GEEHABD; OE wAsEiNeToNnisTEicT-OE COLUMBIA,AssreNoafisY iviEsNE ASSIGNMENTS, TO WTEED RADIO, TNO., OE NEW YORK, N.Y.,A. CORPORATION or` i DELAWARE c c Y. courLiNG SYSTEM EOE HIGHEREOUENOY TEANsMiTTEBs :i

Application meti-December 22,1928.' seriaiNo. 327,952.

My invention relates -to coupling systems showing a balanced thermionictube generain general andmore specifically to coupling tor 1, 2 havinga. quartz y:or mechanically systems employed in high frequency signal-Vibratile element v3 providedfor. maintain-'7. ing Systems, 1 l ing thefrequency characteristicsof constant l5. An object of my Vinventionfistoprovidef value.` .Two thermionic tubes 5 and 6 are as- 55 certainimprovements-in coupling systems'of sociated with the output circuittof` highv the type employed in high frequency transfrequency generator1, 2. Thermionic tubes mtting Systems, i i .4, y 5 andV Glare`connectedina balanced circuit Another object of my invention listoproarrangement, the control electrodes9 and 12.1 vide a coupling systemwhereby. vthe high thereof associated with inductance'l. Cathnefrequency energy of the transmitter may be ode ycircuits 7 and; 10 1 ofi thermionic tubes .i doubled, tripled or quadrupled in frequency. 5-and `6 respectively are energized byv source A Still another object ofmy'inventionis toY of potentiall. Anode electrodes 8 and 11 provide a.coupling system whereby thefreof thermionic tubes5fand 6 respectivelyare el quency of a transmitting system may be do11- Y energized bysource of potential26 by way 6ibled, tripled Or quadrupled andwherebythe of .connector 30, inductance 15', contactsrlt' proper balanceand adjustment of the cir-A and 2O and switch members 19 and 22'respecf`cuits so coupled is assured at each frequency tively. A" source ofpotential. 28.. provides adjustment, i i f the proper operational'.potential for control Other Vand further objects of my inventionelectrodes. 9 and 12 `of* thermionic` tubes -5 70 reside in thefrequency changing system-for and .6', respectively.` Thermionic Vtubes5 hivh frequencytrans'mitters as setforth in and 6 are electricallybalanced by means of.

th` following specification and shown inthe capacities 13 and 14. Thisbalancing ar-` accompanying drawings wherein, Fig. 1 is a rangementprovides the input and output cir'L schematic circuit arrangement of atransmitcuits o f the respective tubes with therproper 75-l ting systememploying the'coupling'system'-` potential and equalizes the energybetween. of my invention' and Figs. 2, and 4 are .A the two. vA capacity33 isprovidedin the; diagrammatic illustrations of the coupling. outputcircuits of thermionic tubes 5 and 6 system of myA invention. Yconnected in `parallel with inductance 15.A A U In a high frequencyradio transmitter deloady circuit 29,27 is associated with induc- 80-rsigned to operate over a large b-and of fretance 15.v Load circuit29,27I is hereinfil-A quencies it is desirable to use balancedcircuits ilustrated as a space radio radiating system.` as the symmetricalarrangement of these* cirv However., it is obvious that additionalamplicuits provide improved operation. .In order fiers, frequencydoublers or4 triplers may `be c that the full frequency ba d maybeemassociated with inductance 15 in like manner. 85 ployed, the vacuumtubes `may be `caused to A rn inductance 25 is provided having'conne'c-`I operate as straight amplifiers,frequency doutions therefrom yto switchmember 24 and blers or frequency triplers depending ont e contacts -18Iand 21. Contact member 23 is part of the frequencyband in which theelectrically .connected to inductance. 15.

that the circuits may be changed from sin-` cally connected tooperateiiiunison. Infthe' gling to doubling or tripling the frequency, circuitarrangement asillustrated, the anode certain connections must bechanged.l Itis circuits of thermionic tubes 5 and 6 are com# i importantthat theL proper adjustments and pleted to inductance 15 by. switchmembers 19` fi balancing are provided on each ofthe freand 22 andcontacts 17 and 20, respectively. .95 quency adjustments. 1t 'isfrequently de- Capacity 35v is provided for excluding high sirable tovemploy a' transmitting system frequency energy from source of potential26.- which may be readily .and efficiently changed The operationof the'coupling system of my tooperate on the ,desiredfrequency.4 1 vinventionis vas follows: Thefinput circuits 1 Figure 1 is `a schematic circuit.diagram of thermionic tubes 5 and areenergizedlbyf Vhigh frequencyenergy from thermionic tubes Y ing'to any even multiple of the frequencyof the input circuit.

- includes inductance 25.

For concreteness of explanation, suppose we assume that the frequency'of the exciting energy is of the order `of 3000 kilocycles and thatinductance 25 is of such a value as ywhen associated with thermionictubes 5 and 6, the frequencycharacteristics of the output circuit willbe of the order'of 6000 kilocycles.` In the accompanying drawings,anodes 8 and l1 of thermionic tubes 55 and Gare connected to switchmembers 19 vand 2,2, respectively, and asillustrated', complete thekanodecircuitsby contacts and inductance 15.

17, and k20, respectively, A change of frequency is easily and quicklyaccomplished by causing switchmembers 19, 24 and 22 to connect withcontact members 18, 23 and 21, respectively.l rlhe latteradjustmentprovides an output circuit for thermicharacteristics are ofthe order of 6000 kilocycles. :The

ergy .from the. circuity including` inductance 25 is transferred to ahigh frequency tank circuit comprising inductance 15 and capacity'33.- Aload. circuit 29-2( may beassocitank circuit 15-33. Frequency valuesofany be obtained by causingswitch vmembers 19 and 22-to engagel withlcontact members 17 and20, respectively, and switch member24 to bedisconnected from contact member 23. The symmetrical arrangement of thecircuits is maintained ateach frequency adjustment.

he frequency value of coil 15 may be simulsociated therewith,

' ling or'quadrupling be had. he characteristics of cuit 27,-29 may besimultaneously varied with each change yof the exciting frequency andcaused to vary with the movement of the common switch member. .Similarcoupling arrangements may be employed for interconnecting any number ofbalanced amplifiers and the symmetrical arrangement of the circuitsmaintained at each frequency adjustment.v 'j j Figs.'2, 3 'and 4 arediagrammatic illustrations showing the coupling system of my inventionin greaterv detail.

6 are adjusted to a frequency` output circuit'in the latter'case Highfrequency enodd `multiple may f mionic tubes.

- a' plurality of the frequency ymay' theload ciroscillatory :circuitsFig. 2 shows the position of the switch members andelectrical circuitfor operating on the fundamental frequency. Figs. 3 and 4 show thepositions of the switch members and the electrical circuit for doublingand triplingA the frequency, respectively. Reference characters shown inFigs. 2, 3 and 4 correspond to'those of Fig'l.

In the accompanying drawings, generators areillustrated as sources ofenergy.v It is obvious thatfany'suitable sourcemay loe employed. Threeelectrode thermionic ltubes are shown, however, lit is obvious thattherving four orimore electrodes mionic tubes ha niayloevemployeV .inthe coupling system of The values of frequency remy invention. .y

foregoing specification `are ferred to in the arbitrary and merelyforthe purpose of explanation. f Y I realize that many vmodifications ofthe coupling system of my invention are possible without departing fromVthe scope of my invention .as defined in the following claims,"and it isunderstood that my invention. shall not bey restricted to theaccompanying drawings or the foregoing specification, but only as de'-iined in the appended claims. j .j

What'I claimas new and desire to secure by Letters Patent of theUnitedStates is as follows: Y Y Y j 1. "In a high frequencytransmittingsystem employing thermio'nic tubes in a balanced c'ircuit arrangementthe combination of a tuned input circuit a plurality of outputcircuitseach having frequency characteristics` differ-- ing from theother such thatthe resonantfrequency of each is some multiple of theresonant frequency of the input circuit, meansfor j impressing upon'saidinput circuita characteristc frequency, a plurality of switch members'associated with said circuits and'ineans for simultaneously actuatingYeach of said switch members whereby said circuits may beinterchangeablyv connected to said ther-l .2. In ak high frequencytransmitting saidftubes a characteristic control frequency, oscillatorycircuits'each having tubes without destroyingrthe symmetry of'lsaidbalanced circuit arrangement.

. 3. In a high frequency transmittingsystem employing aplurality ofthermionic tubes in an electrically the combination kof means forimpressing yon said tubes a contrlfrequency a plurality of each havingfrequency; characteristics differing fromythe other". and

system Vemploying thermionic tubes in a'balanced cirl cuit arrangement,meansfor Vimpressing on such that the resonant frequencyI of eachl isisome multiple of the resonant frequency of the input circuit and meansfor interchangeably associating said oscillatory circuits with saidthermionic tubes whereby the Symmetry of said balanced circuit arrangemet is maintained.

4. In a high frequency transmitting system employing a plurality ofthermionic tubes in a balanced circuit arrangement, the combination ofmeans for impressing on said tubes a control frequency, a plurality ofoscillatory circuits each having frequency characteristics differingfrom the other and such that the resonant frequency of each is somemultiple of the resonant frequency of the input circuit and means forinterchangeably associating said oscillatory circuits with saidthermionic tubes.

5. In a high frequency employing thermionic tubes in a balanced circuitarangement, means for impressing on said tubes a control frequency, anoscillatory circuit having a resonant frequency that is a multiple ofsaid control frequency associated with said thermionic tubes. a loadcircuit associated with said oscillatory circuit, a second oscillatorycircuit having frequency charn acteristics differing from said firstmentioned oscillatory circuit having a resonant frequency that isanother multiple of said control frequency and means for associatingsaid last mentioned circuit with said thermionic tubes andsimultaneously connecting the electrical centers of said oscillatorycircuits.

6. In combination two thermionic vacuum tubes each having cathode, anodeand control electrodes, an inductance interconnecting the gridelectrodes of said tubes, means for impressing on said inductance afundamental.

frequency, a. plurality of resonant circuits adapted to be connected inthe anode circuit of said tubes, each said resonant circuit beinresonant to a different frequency and eac said frequency being somemultiple of said fundamental frequency and means for selectivelyconnecting said resonant circuits one at .a time in the anode circuit ofsaid tubes whereby different frequency .multiplications may be made.

7. In a high frequency transmitting system employing thermionic tubes inan electrically balanced circuit arrangement, an in ut circuit for saidtubes, means for impressing on said input circuit a control frequency anoutput circuit associated with said tubes, a load circuit associatedwith said output circuit, an oscillatory circuit Vhaving a resonantfrequency that is a multiple of said control frequency, means forinterchangeably associating said output circuit and said oscillatorycircuit with said thermionic tubes and means for simultaneouslyassociating said output circuit and said oscillatory circuit.

LOUIS A. GrEBIIARI).V

transmitting system i

